Vibrations of Formaldehyde, CH2O, Vibration 2 (Home)

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Using PM6, the sixth vibrational mode of formaldehyde, A1, occurs at 2668cm-1.    This corresponds to a vibrational period of 1/(2668x3x1010) seconds, or
12.5x10-15 s, or 12.5 femtoseconds.  This is an unsymmetrical vibration.

In this simulation, each frame represents 0.2 fs, and the display is 50 frames per second, so each second represents 10fs.  If, using a stopwatch,  you time all 10 complete vibrations, it'll come to about 12.5 seconds, therefore the simulation represents a total of 125fs.  In fact, from the output, the total time is 125.8fs. From this it follows that each vibration takes about 12.58 fs, and has a frequency of 1/(3x1010x12.58x10-15) cm-1 or 2650 cm-1  in reasonably good accordance with the results of the vibrational calculation.

Data set used by MOPAC:

   irc=6 drc cycles=1113 t-priority=0.2
 Formaldehyde

  O         0.00000000 +0    0.0000000 +0    0.0000000 +0                     -0.4225
  C         1.21074828 +1    0.0000000 +0    0.0000000 +0    1    0    0       0.2366
  H         1.09713884 +1  122.0336155 +1    0.0000000 +0    2    1    0       0.0929
  H         1.09712655 +1  122.0249758 +1  180.0000000 +0    2    1    3       0.0929